package de.dopichaj.labrador.index;

import java.util.HashMap;
import java.util.Map;
import java.util.Stack;

/**
 * The XPathStack assumes that everything thrown on the stack is both
 * a String and also a markup element. It contains a hashtable to keep 
 * track of the XPath of the current element and returns it with its
 * toString() method.
 * @author Benedikt
 */
public class XPathStack extends Stack<String> {

    private static final long serialVersionUID = 4806945853146191212L;

    /**
     * A hashtable to keep track of the xpath of the nodes
     */
    private final Map<String, Integer> xPathTracker = new HashMap<String, Integer>();
    
    /**
     * Puts a markup-element on the stack.
     */
    @Override
    public String push(String item) {
        // XPath processing using a hashtable
        String currentXPath = this.toString() + "/" + item;
        if(xPathTracker.containsKey(currentXPath)) {
            int n = xPathTracker.get(currentXPath);
            xPathTracker.put(currentXPath, n + 1);
        } else {
            xPathTracker.put(currentXPath, 1);
        }

        // calling the superclass for normal stack functionality
        return super.push(item);        
    }
    
    /**
     * Returns the XPath that currently represents
     * the element on top of the stack.
     */
    @Override
    public String toString() {
        StringBuffer xPath = new StringBuffer();
        for (String pathPart : this) {
            xPath.append("/").append(pathPart);
            int n = xPathTracker.get(xPath.toString());
            xPath.append("[").append(n).append("]");
        }
        return xPath.toString();        
    }
    
}
/*
Copyright (c) 2005 Benedikt Eger
Copyright (c) 2005-2007 Philipp Dopichaj

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/